aboutsummaryrefslogtreecommitdiff
path: root/src/uint256.cpp
blob: c58c88bf4a8f145b921f5fed2312e055651d29a4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2015 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include "uint256.h"

#include "utilstrencodings.h"

#include <stdio.h>
#include <string.h>

template <unsigned int BITS>
base_blob<BITS>::base_blob(const std::vector<unsigned char>& vch)
{
    assert(vch.size() == sizeof(data));
    memcpy(data, &vch[0], sizeof(data));
}

template <unsigned int BITS>
std::string base_blob<BITS>::GetHex() const
{
    char psz[sizeof(data) * 2 + 1];
    for (unsigned int i = 0; i < sizeof(data); i++)
        sprintf(psz + i * 2, "%02x", data[sizeof(data) - i - 1]);
    return std::string(psz, psz + sizeof(data) * 2);
}

template <unsigned int BITS>
void base_blob<BITS>::SetHex(const char* psz)
{
    memset(data, 0, sizeof(data));

    // skip leading spaces
    while (isspace(*psz))
        psz++;

    // skip 0x
    if (psz[0] == '0' && tolower(psz[1]) == 'x')
        psz += 2;

    // hex string to uint
    const char* pbegin = psz;
    while (::HexDigit(*psz) != -1)
        psz++;
    psz--;
    unsigned char* p1 = (unsigned char*)data;
    unsigned char* pend = p1 + WIDTH;
    while (psz >= pbegin && p1 < pend) {
        *p1 = ::HexDigit(*psz--);
        if (psz >= pbegin) {
            *p1 |= ((unsigned char)::HexDigit(*psz--) << 4);
            p1++;
        }
    }
}

template <unsigned int BITS>
void base_blob<BITS>::SetHex(const std::string& str)
{
    SetHex(str.c_str());
}

template <unsigned int BITS>
std::string base_blob<BITS>::ToString() const
{
    return (GetHex());
}

// Explicit instantiations for base_blob<160>
template base_blob<160>::base_blob(const std::vector<unsigned char>&);
template std::string base_blob<160>::GetHex() const;
template std::string base_blob<160>::ToString() const;
template void base_blob<160>::SetHex(const char*);
template void base_blob<160>::SetHex(const std::string&);

// Explicit instantiations for base_blob<256>
template base_blob<256>::base_blob(const std::vector<unsigned char>&);
template std::string base_blob<256>::GetHex() const;
template std::string base_blob<256>::ToString() const;
template void base_blob<256>::SetHex(const char*);
template void base_blob<256>::SetHex(const std::string&);

static void inline HashMix(uint32_t& a, uint32_t& b, uint32_t& c)
{
    // Taken from lookup3, by Bob Jenkins.
    a -= c;
    a ^= ((c << 4) | (c >> 28));
    c += b;
    b -= a;
    b ^= ((a << 6) | (a >> 26));
    a += c;
    c -= b;
    c ^= ((b << 8) | (b >> 24));
    b += a;
    a -= c;
    a ^= ((c << 16) | (c >> 16));
    c += b;
    b -= a;
    b ^= ((a << 19) | (a >> 13));
    a += c;
    c -= b;
    c ^= ((b << 4) | (b >> 28));
    b += a;
}

static void inline HashFinal(uint32_t& a, uint32_t& b, uint32_t& c)
{
    // Taken from lookup3, by Bob Jenkins.
    c ^= b;
    c -= ((b << 14) | (b >> 18));
    a ^= c;
    a -= ((c << 11) | (c >> 21));
    b ^= a;
    b -= ((a << 25) | (a >> 7));
    c ^= b;
    c -= ((b << 16) | (b >> 16));
    a ^= c;
    a -= ((c << 4) | (c >> 28));
    b ^= a;
    b -= ((a << 14) | (a >> 18));
    c ^= b;
    c -= ((b << 24) | (b >> 8));
}

uint64_t uint256::GetHash(const uint256& salt) const
{
    uint32_t a, b, c;
    const uint32_t *pn = (const uint32_t*)data;
    const uint32_t *salt_pn = (const uint32_t*)salt.data;
    a = b = c = 0xdeadbeef + WIDTH;

    a += pn[0] ^ salt_pn[0];
    b += pn[1] ^ salt_pn[1];
    c += pn[2] ^ salt_pn[2];
    HashMix(a, b, c);
    a += pn[3] ^ salt_pn[3];
    b += pn[4] ^ salt_pn[4];
    c += pn[5] ^ salt_pn[5];
    HashMix(a, b, c);
    a += pn[6] ^ salt_pn[6];
    b += pn[7] ^ salt_pn[7];
    HashFinal(a, b, c);

    return ((((uint64_t)b) << 32) | c);
}